Custom Evaluation Benchmarks
As companies ship more production LLM features, silent provider-side model and prompt-layer changes (like the April 2026 Anthropic Claude Code regression) are causing undetected quality drops that generic eval platforms don't catch because they lack company-specific test cases — creating demand for a service that builds and maintains a custom benchmark tied to each client's actual workflow.
Strong, dated real-world evidence of silent model regressions plus a clear tooling gap (eval platforms provide the scoring engine, not the client-specific test cases) makes this a credible high-margin consulting-to-retainer business, though it depends on the founder's own technical credibility to close deals and currently has no productized self-serve path, keeping scalability moderate rather than software-level.
Braintrust ($0-$249/mo) and LangSmith ($0-$99/mo) charge for the scoring/tracing infrastructure, and Promptfoo is free and open-source — none of them ship a client's specific test cases, meaning every team still has to build their own benchmark by hand or skip it entirely. Anthropic's confirmed April 2026 Claude Code regression (caused by reasoning-effort and prompt changes, not a model weight update) and the wider documented 'silent versioning problem' across providers give concrete, citable proof that teams are shipping without regression coverage; a service that turns 2-4 weeks of discovery into a maintained 50-150 case benchmark addresses exactly that gap at a price point ($5K-$30K build, $2K-$8K/mo monitoring) well below what an internal ML hire would cost.
Demand ticks up around major model provider release windows (new flagship model launches) when clients most fear a forced or silent swap.
Suits you if
- ✓You've built production LLM applications and personally debugged a model-swap or prompt-drift regression
- ✓You can run structured client interviews to extract failure modes rather than just operate eval software
- ✓You're comfortable both writing evaluation code and running consultative sales conversations
- ✓You want a path from one-off project fees into recurring monitoring retainer revenue
Skip it if
- ✕You want a purely productized, no-sales-conversation offer from day one
- ✕You don't have credibility to speak to engineering leaders about their model pipeline specifics
- ✕You're not willing to do the unglamorous work of manually reviewing a client's production logs to build test cases
- ✕You need fast, predictable revenue rather than a consulting sales cycle of several weeks
Skills: LLM application development (prompting, RAG, agent tool-calling), eval tooling (Promptfoo, Braintrust, or LangSmith), scripting in Python for test harnesses, CI/CD basics for automated re-runs, and consultative B2B sales to close project and retainer deals.
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